FIGURE 1.

mAb 3d-8b is able to block CR2/C3d interaction in vivo and diminish a T-dependent immune response. (A) Thirty wild-type B6 mice were split into three groups and preinjected with 1.5 mg/mouse mAb 3d-8b (10 mice), nonblocking CR2/C3d mAb 3d-11 (10 mice), or PBS (10 mice). Eighteen hours later, mice in each group were immunized i.p. with the T-dependent Ag SRBC at 1 × 10⁷ SRBC per mouse. Ab production to SRBC, both IgM and IgG1, was analyzed on day 17. In (B), the same mice were boosted later with the same amount of SRBC on day 34, and blood samples were taken 10 d later for the ELISA analysis. Bars represent average (mean) R.U. data calculated for all 10 mice of one particular group. Error bars represent SD. Data are representative of two independent experiments. Statistical analyses were performed by one-way ANOVA. *p < 0.05. ns, not statistically significant.